Bug#22646 LC_TIME_NAMES: Assignment to non-UTF8 target fails

Problem: After introducing of LC_TIME_NAMES variable,  the 
function date_format() can return international non-ascii
characters in month and weekday names. Thus, it cannot return
a binary string anymore, because inserting a result of date_format()
into a column with non-utf8 character set produces garbage.
Fix: date_format() now returns a character string, using
"collation_connection" to detect character set and collation
for the returned value. This allows to insert
results of date_format() properly into columns with
various character sets.


mysql-test/r/ctype_utf8.result:
  Adding test case.
  Fixing old result.
mysql-test/t/ctype_utf8.test:
  Adding test case.
sql/item_timefunc.cc:
  DATE_FORMAT() now returns a character string
  instead of binary string:
  - make_date_time() now converts localte data from UTF8 to 
  the character set of "str" argument, instead of copying as is.
  - fix_dec_and_length() now uses "collation_connection"
  instead of "binary" for the result, it also now
  multiplies to mbmaxlen when calculating max_length

2 files changed, 43 insertions, 1 deletions

diff --git a/mysql-test/r/ctype_utf8.result b/mysql-test/r/ctype_utf8.result
index fdf21a50a02..24f29b23e87 100644
--- a/mysql-test/r/ctype_utf8.result
+++ b/mysql-test/r/ctype_utf8.result
@@ -124,12 +124,34 @@ create table t1 select date_format("2004-01-19 10:10:10", "%Y-%m-%d");
 show create table t1;
 Table	Create Table
 t1	CREATE TABLE `t1` (
-  `date_format("2004-01-19 10:10:10", "%Y-%m-%d")` binary(10) default NULL
+  `date_format("2004-01-19 10:10:10", "%Y-%m-%d")` char(10) character set utf8 default NULL
 ) ENGINE=MyISAM DEFAULT CHARSET=latin1
 select * from t1;
 date_format("2004-01-19 10:10:10", "%Y-%m-%d")
 2004-01-19
 drop table t1;
+set names utf8;
+set LC_TIME_NAMES='fr_FR';
+create table t1 (s1 char(20) character set latin1);
+insert into t1 values (date_format('2004-02-02','%M'));
+select hex(s1) from t1;
+hex(s1)
+66E97672696572
+drop table t1;
+create table t1 (s1 char(20) character set koi8r);
+set LC_TIME_NAMES='ru_RU';
+insert into t1 values (date_format('2004-02-02','%M'));
+insert into t1 values (date_format('2004-02-02','%b'));
+insert into t1 values (date_format('2004-02-02','%W'));
+insert into t1 values (date_format('2004-02-02','%a'));
+select hex(s1), s1 from t1;
+hex(s1)	s1
+E6C5D7D2C1CCD1	Февраля
+E6C5D7	Фев
+F0CFCEC5C4C5CCD8CEC9CB	Понедельник
+F0CEC4	Пнд
+drop table t1;
+set LC_TIME_NAMES='en_US';
 set names koi8r;
 create table t1 (s1 char(1) character set utf8);
 insert into t1 values (_koi8r'��');
diff --git a/mysql-test/t/ctype_utf8.test b/mysql-test/t/ctype_utf8.test
index af40121852f..0b3f9ed2400 100644
--- a/mysql-test/t/ctype_utf8.test
+++ b/mysql-test/t/ctype_utf8.test
@@ -94,6 +94,26 @@ select * from t1;
 drop table t1;
 
 #
+# Bug#22646 LC_TIME_NAMES: Assignment to non-UTF8 target fails
+#
+set names utf8;
+set LC_TIME_NAMES='fr_FR';
+create table t1 (s1 char(20) character set latin1);
+insert into t1 values (date_format('2004-02-02','%M'));
+select hex(s1) from t1;
+drop table t1;
+create table t1 (s1 char(20) character set koi8r);
+set LC_TIME_NAMES='ru_RU';
+insert into t1 values (date_format('2004-02-02','%M'));
+insert into t1 values (date_format('2004-02-02','%b'));
+insert into t1 values (date_format('2004-02-02','%W'));
+insert into t1 values (date_format('2004-02-02','%a'));
+select hex(s1), s1 from t1;
+drop table t1;
+set LC_TIME_NAMES='en_US';
+
+
+#
 # Bug #2366  	Wrong utf8 behaviour when data is truncated
 #
 set names koi8r;